Dependency injection in MVC

Today I would like to share my thoughts on dependency injection in MVC. If you are not familiar with MVC, i would suggest to read my article about MVC first.

What is Dependency Injection?

In simple words dependency injection (DI) means injecting a new functionality (let say X) to a base functionality without making any changes it. Later, functionality X can be replaced by Functionality Y with no impact on base functionality.